[FLASH-BUGS] Cosmology unit zeroes out all mass

[Aaron Froese]

Dear FLASH Team,

I find that any FLASH3.3 simulation that includes the Cosmology unit has zero mass/density for all time.  I can reproduce this behaviour in the Pancake example problem as well as when I add "REQUESTS physics/Cosmology" to the Config file of other example problems like magnetoHD/BlastBS or Sedov.

Thank-you,
Aaron